/*
 * Copyright (c) 2012, marco.tamburelli@gmail.com
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met: 
 * 
 * 1. Redistributions of source code must retain the above copyright notice, this
 *    list of conditions and the following disclaimer. 
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution. 
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.bmi.gwt.mi.server.util;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

class ClassProvider
{
	private Map<String, List<String>> classMap;
	private ArrayList<Class<?>> subTypes;

	ClassProvider(Map<String, List<String>> classMap)
	{
		this.classMap = classMap;
		this.subTypes = new ArrayList<Class<?>>(10);
	}

	/**
	 * Returns requested results in other words subclasses of provided parent
	 * class.
	 * 
	 * @param parentType The parent type.
	 * @return
	 */
	@SuppressWarnings("unchecked")
	public <T> List<Class<? extends T>> getSubTypesOf(Class<T> parentType)
	{
		/* generating the list of sub types by provided parent type */
		extractSubTypes(parentType.getName());

		List<Class<? extends T>> fetchedTypes = new ArrayList<Class<? extends T>>(10);

		for (Class<?> t : this.subTypes)
			fetchedTypes.add((Class<? extends T>) t);

		this.subTypes.clear();

		return fetchedTypes;
	}

	private void extractSubTypes(String type)
	{
		if (this.classMap.containsKey(type)) for (String t : this.classMap.get(type))
			try
			{
				this.subTypes.add(Class.forName(t));
				extractSubTypes(t);
			}
			catch (ClassNotFoundException e)
			{
				/* If the class is not found nothing we will add */
			}
	}
}
